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MBTA gets cracking on third-rail inspections

The Globe reports MBTA General Manager Beverly Scott has ordered an audit of all the third rails on the Red, Orange and Blue lines to try to stave off the sort of problems that bollixed commutes on the Red Line Wednesday morning and Tuesday evening.

Carl Stevens reports the inspections will focus on the welds that connect sections of the third rail together.

Hasn't the ENTIRE Orange Line been due for a third rail replacement for YEARS now? Yes, that's right, the ENTIRE length. I'm sure parts of the Red Line are just the same. But lets pretend we didn't know anything about this and initiate an audit.

The rail used for third rail usually can last decades, the wear and tear is nowhere near the level found with running rails (the ones the wheels are actually on). Both of these failures occurred in an area where a major signal and track reconstruction project (including replacing the third rail) has been going on for over a year. The issue at this specific location might not be the age of the rail at all, but rather if new third rail was installed properly and meets specifications to begin with, or if existing third rail that has not been replaced yet was damaged from the nearby construction. Note that on just the previous weekend of December 7-8, there was a planned shuttle bus operation going on between Broadway and JFK/U Mass to accommodate construction in this very segment where the two failures took place.

If the power is lost the train would cycle into emergency and the brakes would be applied, stopping the train, and not softly either. A crack in a 3rd rail is almost unheard of.

A crack in a 3rd rail is not immediately serious due to connective redundancy but if the level of the rail shifts it could snag the 3rd rail pickup shoe on the train causing damage. Then you'd see a really extended period of bussing replacements until the train was towed out.

...and it will probably turn out that the words "all-night poker tournament" were prominently involved, but they also might need all hands on deck to clean 1,452 copies of the Metro* and 841 Dunkies cups out of each and every subway car.

*anyone who wants to join me in calling the Metro "litterature" will be greatly appreciated

Hit the rail with a sledgehammer and see if it moves or a crack opening can be seen? Perhaps also attach multimeter leads on each side of a weld and see if impedance jumps? Run a train (slowly) down the track, noting if power is lost/drops at any point? A train engineer, I would think, reports inconsistent power on the track, (then maintenance gets right on that!).